LAUSR

Effects of egg storage length and orientation on hatching traits and spread of hatch were determined in Transylvanian naked neck chicken. Eggs (n=640) stored in a cold room (16±1.5o C, 75±1.5% RH) in batches of 160 eggs each, for 1, 3, 5 or 7d were used. Half of each batch was stored with a broad end up (BEU) and the other in a narrow end up (NEU). Eggs were incubated in a two-stage incubator (37.5o C, 64% RH). Storage length caused a significant increase in egg weight loss (EWL; P<0.001). Egg fertility (FERT) was significantly lower in 7d than in 1, 3 and 5d stored eggs (P<0001). Dead in shell (DIS) was lower (P<0.001) in 1d storage than in other lengths (P<0.001). Hatchability of total (HSE) and fertile eggs (HFE) decreased (P>0.001) gradually from 1 to 7d, though 3 and 5d were found to be similar. Hatching commenced earlier (P=0.055) in 5d than 1d storage. Incubation time at 100% hatch, hatch window and spread of hatch were not (P>0.05) affected by storage length. At the end of the hatch, longer storage than 1d caused 45, 45 and 15 min/d delay in hatching for 3, 5 and 7d storage respectively. The chicks from 3d storage (17.3cm) were longer (P=0.05) than those from 5 (17.1cm) and 7d groups (17.1cm). Higher DIG and DIS but lower HSE and HFE (P<0.05) were recorded in BEU than in NEU orientation. Earlier commencement of hatch (CH) was recorded in BEU than in NEU eggs. There were significant (P<0.05) interactions between storage length and orientation in FERT, DIG, HSE, HFE, CH and hatch window. To achieve HFE up to 70%, eggs could be stored for up to 7d in NUE orientation but should not exceed 3d in BEU orientation. This article is protected by copyright. All rights reserved.